Conventional vehicle communication systems, in order to send a message to a control unit, are designed to attach, to the message to be sent, an address identifying the control unit.
In addition, in vehicle diagnosis monitoring, an operator communicably connects, to an in-vehicle communication network, a diagnosis monitoring device, such as a diagnosis monitoring tool. Next, the operator operates an enter key and the like of the diagnosis monitoring device to enter, into the diagnosis monitoring device, information indicative of a control unit (target control unit) in which a target function is installed beforehand and of descriptions associated with diagnosis monitoring of the target function. The descriptions are to instruct the target control unit what the operator wants to monitor and diagnose regarding the target function.
In response to the information entry, the diagnosis monitoring device sends, to the target control unit, request messages identifying the target control device as its destination and requesting it to execute diagnosis monitoring of the target function in accordance with the descriptions.
Note that the request messages for diagnosis monitoring include a data request message that requests a target control unit to execute a function of returning control data stored therein and/or a drive request message that requests a target control unit to execute a function of forcibly driving an actuator. The actuator is configured to put in-vehicle devices into automatic action, such as force or motion.
Techniques associated with routers that connect a plurality of different networks to each other are disclosed in European Unexamined Patent Publication No. EP1039725A2 corresponding Japanese Unexamined Patent Publication No. 2000-244549.
In the conventional vehicle diagnosis monitoring set forth above, an operator to manipulate the diagnosis monitoring device, in other words, an operator to perform vehicle diagnosis monitoring needs to previously grasp which functions are installed in advance in which of the control units. This may cause the diagnosis monitoring work to become complicated.
Specifically, hardware standardization among communication systems installed in vehicles is being promoted, which produces an improvement in the portability of applications to realize various types of functions.
For these reasons, even if the functions are the same as each other, they may be installed in different control units depending on the vehicle models. In addition, even if vehicles have the same model, depending on their different grades and/or their different options, they may have different functions installed therein and/or may have different numbers of functions installed therein.